US6874705B2 - Noise-optimized device for injecting fuel - Google Patents

Noise-optimized device for injecting fuel Download PDF

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US6874705B2
US6874705B2 US10/372,316 US37231603A US6874705B2 US 6874705 B2 US6874705 B2 US 6874705B2 US 37231603 A US37231603 A US 37231603A US 6874705 B2 US6874705 B2 US 6874705B2
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chamber
pressure
storage
return flow
piston
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US20030178001A1 (en
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Marcus Parche
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M45/00—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • F02M45/02—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
    • F02M45/04—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
    • F02M45/08—Injectors peculiar thereto
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M55/00—Fuel-injection apparatus characterised by their fuel conduits or their venting means; Arrangements of conduits between fuel tank and pump F02M37/00
    • F02M55/04—Means for damping vibrations or pressure fluctuations in injection pump inlets or outlets
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/44—Details, components parts, or accessories not provided for in, or of interest apart from, the apparatus of groups F02M59/02 - F02M59/42; Pumps having transducers, e.g. to measure displacement of pump rack or piston
    • F02M59/46—Valves
    • F02M59/466—Electrically operated valves, e.g. using electromagnetic or piezoelectric operating means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F02M61/20—Closing valves mechanically, e.g. arrangements of springs or weights or permanent magnets; Damping of valve lift
    • F02M61/205—Means specially adapted for varying the spring tension or assisting the spring force to close the injection-valve, e.g. with damping of valve lift
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
    • F02M2200/04—Fuel-injection apparatus having means for avoiding effect of cavitation, e.g. erosion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
    • F02M2200/30—Fuel-injection apparatus having mechanical parts, the movement of which is damped
    • F02M2200/304—Fuel-injection apparatus having mechanical parts, the movement of which is damped using hydraulic means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M53/00—Fuel-injection apparatus characterised by having heating, cooling or thermally-insulating means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M55/00—Fuel-injection apparatus characterised by their fuel conduits or their venting means; Arrangements of conduits between fuel tank and pump F02M37/00
    • F02M55/007—Venting means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M57/00—Fuel-injectors combined or associated with other devices
    • F02M57/02—Injectors structurally combined with fuel-injection pumps
    • F02M57/022—Injectors structurally combined with fuel-injection pumps characterised by the pump drive
    • F02M57/023—Injectors structurally combined with fuel-injection pumps characterised by the pump drive mechanical
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/20—Varying fuel delivery in quantity or timing
    • F02M59/36—Varying fuel delivery in quantity or timing by variably-timed valves controlling fuel passages to pumping elements or overflow passages
    • F02M59/366—Valves being actuated electrically
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/14—Arrangements of injectors with respect to engines; Mounting of injectors

Definitions

  • component parts such as switching valves and injection nozzles in high-pressure pumps and in the various embodiments of injectors, nozzle holder combinations, or unit injector systems are made to move. Their motion positively displaces a volume which is replenished on the intake side. For the requisite volumetric flow, the pressures and cross sections must be adapted. If the replenishment of fuel is inadequate, the pressure on the intake side drops. If the vapor pressure of the fluid to be pumped fails to be attained, the column of liquid breaks off, causing cavitation bubbles to form. Upon recompression of the fuel to above the vapor pressure, the collapse of the vapor bubbles causes noise.
  • unit injector systems in self-igniting internal combustion engines, mechanically-hydraulically controlled preinjection phases are generated, which contribute on the one hand to reducing the noise of combustion and on the other to minimizing pollutants.
  • a pump piston is moved upward via a restoring spring.
  • the fuel which is at a constant overpressure, flows out of the low-pressure part of the fuel supply via the inlet bores, which are integrated with the engine block, and via the inlet conduit into the magnet valve chamber.
  • the magnet valve is opened. Via a connecting bore, the fuel reaches the high-pressure chamber.
  • the pump piston moves downward.
  • the magnet valve remains in its open position, and the fuel is forced by the pump piston via the inlet conduit back into the low-pressure part of the fuel supply.
  • an actuator is triggered by the control unit at a specified instant, so that the actuator is pulled into a seat, and the communication between the high-pressure chamber and the low-pressure part is closed.
  • This instant is also known as the “electrical injection onset”.
  • the high fuel pressure in the high-pressure chamber rises continuously as a result of the motion of the pump piston, and as a result a rising pressure is also established at the injection nozzle.
  • This instant is also called the “actual injection onset”, or the supply onset. Because of the high pumping rate of the pump piston, the pressure continues to rise during the entire injection event.
  • the actuator In a concluding operating state, the actuator is turned off again, after which the actuator opens after a slight delay, and the communication between the high-pressure chamber and the low-pressure part is opened again.
  • the actuator magnet valves or piezoelectric actuators can for instance be used.
  • the peak pressure is reached. After that, the pressure collapses very quickly. When it falls below the nozzle closing pressure, the injection nozzle closes and terminates the injection event. The remaining fuel pumped by the pump element until the apex point of the driving cam is forced into the low-pressure part via the return conduit.
  • Single-pump systems of the kind described above are intrinsically safe; that is, in the unlikely event of a fault or defect, no more than one uncontrolled injection can occur: If the magnet valve opens, injection cannot occur, since the flows back into the low-pressure part, and a pressure buildup cannot occur. Since the filling of the high-pressure chamber takes place exclusively via the actuator, when the actuator remains constantly in the closed state no fuel can reach the high-pressure chamber.
  • unit injector systems are built into the cylinder head and exposed to high temperatures. To keep the temperatures in the unit injector system as low as possible, cooling of the components of the unit injector system is as a rule done by means of fuel, which in turn flows back into the low-pressure part of the fuel injection system.
  • the total pressure p tot of a flowing medium is composed of a static pressure component p stat and a dynamic pressure component p dyn . Except for pressure losses, caused for instance by friction, the total pressure established is constant.
  • the fuel passes through a throttle, whose cross section has a certain value. If the throttle is enlarged, a residual pressure can be maintained as a function of the flow cross section. If the positively displaced volumetric flow is greater than the replenishing quantity, then the pressure in the spring holder drops. If when the pressure in the spring holder drops it drops below the vapor pressure, cavitation can occur.
  • European Patent Disclosure EP 0 404 916 B1 has a fuel injection nozzle as its subject.
  • the fuel injection nozzle embodied in particular as a pump-nozzle, includes a nozzle needle, which is urged in the closing direction by a spring.
  • a pressure chamber upstream of the seat of the nozzle needle is in communication with a storage chamber that is defined by a spring-loaded compensation piston.
  • the compensation piston also called a storage piston
  • the storage chamber is located downstream of this sealing seat, as viewed from the pressure chamber.
  • the storage piston which has a cylindrical guide part, is subjected, on its end remote from the storage chamber, to the pressure in a damping chamber that can be filled with fuel, and it has a peg which dips into a plate that defines the damping chamber and has an opening.
  • the cylindrical guide part of the storage piston has a ratio of the diameter to the height of 1:0.1 to 1:0.4; the peg of the storage piston has a variable cross section that dips into the boundary plate, and on its end toward the storage chamber, the storage piston has a guide extension with grooves.
  • a delay in the storage piston return motion can be achieved, yet without significantly impairing the opening motion of the storage piston inside a unit injector system.
  • a return flow throttle valve can be disposed in the region of the high-pressure communication of the storage chamber.
  • the return flow throttle valve is passable, viewed in the opening direction of the storage piston, so that the hydraulically controlled preinjection is unimpaired. After the end of the main injection, the high-pressure in the entire high-pressure volume drops so far that the closing pressure level of the storage piston is reached. When the closing pressure level is reached, the closing motion of the storage piston begins. If a return flow throttle valve is used, a pressure difference is established between the pressure on the storage piston side of the return throttle and the pressure on the high-pressure side, and this pressure difference causes a closure of the return throttle. A pressure reduction can in this case only occur in delayed fashion via the throttle restriction itself, so that the return motion is slowed down sharply.
  • the reverse motion of the storage piston that is, the component motion that is definitive for the cavitation phenomena, can be delayed to such an extent that a replenishing flow of fuel into the interior of the spring holder occurs without cavitation, so that noise does not develop.
  • a check valve can be used in the unit injector system. Toward the end of the injection, the pressure on the high-pressure side drops, whereupon the check valve closes. The pressure in the reservoir remains at a high level, so that the storage piston remains in its open position. Leaks for production and tolerance reasons at the storage piston guide causes slow reduction in the pressure, until it drops below the closing pressure of the reservoir, and the storage piston closes slowly.
  • FIG. 1 shows the general layout of a unit injector system for supplying fuel to the combustion chambers of a self-igniting internal combustion engine
  • FIG. 1 a is an enlarged view of the fluidic communication between the storage chamber and the hollow chamber of the spring holder in the prior art shown in FIG. 1 ;
  • FIG. 2 shows the return flow throttle unit, disposed between the storage piston chamber and the hollow spring holder chamber, for delaying the closing motion of the storage piston;
  • FIG. 3 shows the storage piston in its closed position
  • FIG. 4 shows the opening of the sealing seat of the storage piston when its opening pressure is reached
  • FIG. 5 shows the sealing off of a hollow chamber in the injector by an end face facing the sealing seat of the storage piston.
  • a pump piston 3 which is received movably in a pump body 4 , is actuated via a spherical bolt 1 .
  • the spherical bolt 1 in turn is actuated via a tiltably disposed tilt lever 28 , which is provided on one of its ends with a rotatably supported roller body.
  • the roller body rolls along a cam of a driving camshaft 27 .
  • the deflection of the tilt lever 28 about its pivot axis depends on the course of the shaping of the top of the cam, which in the view of FIG. 1 extends eccentrically to the pivot axis of the driving camshaft 27 .
  • the pump piston 3 of the pump body 4 of the unit injector system is acted upon by a restoring spring 2 , which is braced on one end on a plane face of the pump body 4 and on the other on a caplike support element, which is disposed in the upper region of the pump piston 3 that is movable in the pump body 4 .
  • an actuator which in the exemplary embodiment shown in FIG. 1 includes a magnet coil 10 .
  • the magnet coil 10 of the actuator acts on an armature 9 , which in turn acts on a magnet valve needle.
  • the armature 9 of the actuator is acted upon by a compensation spring 7 .
  • Reference numeral 6 indicates the magnet core, which surrounds the magnet coil 10 of the actuator.
  • a fuel return 11 is shown below the actuator; by way of it, excess fuel flowing out of the unit injector system can return into a low-pressure region, not further shown in FIG. 1 , such as the tank of a motor vehicle.
  • the unit injector system In the fastening region at the cylinder head of the engine, the unit injector system is sealed off by way of sealing elements 12 .
  • inlet bores 13 are embodied in the wall, and by way of them fuel flows from a low-pressure-side fuel forward flow, to a valve chamber of an actuator, embodied here as a magnet valve, to the element chamber 25 .
  • fuel is conducted through the pump body 4 for cooling the actuator and, via a bore system embodied in the pump body 4 , it reaches a chamber defined by two sealing rings 12 , and from there it is carried away via the fuel return marked 11 .
  • the leak fuel in the pump piston 3 can be carried away; moreover, by means of throttle restrictions embodied in the return system, vapor bubbles can be removed.
  • Reference numeral 14 indicates a hydraulic stop, which functions as a damper. Extending below the hydraulic stop is a nozzle needle 18 , which is partly surrounded by an integrated injection nozzle body 20 .
  • the nozzle needle 18 in its front region pointing toward a combustion chamber 17 , is seated inside a needle seat 15 .
  • a lock nut 19 By means of a lock nut 19 , the unit injector system and the integrated injection nozzle 20 partly surrounding the nozzle needle 18 communicate with one another; below the lock nut 19 , there is a sealing disk 16 , for sealing off the combustion chamber 17 of a self-igniting internal combustion engine from the cylinder head of the engine.
  • the cylinder head of the self-igniting engine is marked 21 .
  • a hollow chamber 42 of a spring holder which receives a compression spring 22 , embodied for instance as a spiral spring.
  • the compression spring 22 is braced by its lower end on a disklike insert in the hollow chamber 42 of the spring holder, and with its opposite end it acts on a storage piston 23 .
  • the storage piston 23 embodied for instance in two parts, including a peglike element and a disk, is enclosed inside the unit injector system by a storage chamber 24 .
  • the disk can be embodied as a separate component.
  • the storage chamber 24 of the storage piston 23 and the hollow chamber 42 of the spring holder are in fluidic communication with one another, via an opening 31 shown enlarged in FIG. 1 a.
  • the pump piston 3 which is movable vertically up and down via the tilt lever 28 , acts upon a high-pressure chamber 25 within the unit injector system, which is also known as an element chamber.
  • a high-pressure inlet branches off to the nozzle chamber and acts upon the nozzle needle 18 on the end toward the cylinder head of the unit injector system.
  • the fuel which is at high pressure, flows via an annular gap in the direction of the needle seat 15 , and from there, upon an upward motion of the nozzle needle 18 , it is injected into the combustion chamber 17 of the self-igniting engine within a preinjection and a main injection.
  • reference numeral 26 indicates a magnet valve spring, which urges the magnet valve needle 8 in the restoring direction.
  • FIG. 1 a an enlarged view of the region of the unit injector system shown in FIG. 1 can be seen, in which the opening 31 between the storage chamber and the hollow chamber of the spring holder is shown on a larger scale.
  • the storage piston 23 is surrounded by the storage chamber 24 and is acted upon by fuel, which is at high pressure, from the high-pressure side that is emerging from the high-pressure chamber 25 .
  • fuel which is at high pressure
  • the fuel in the hollow chamber of the spring holder 42 is compressed.
  • the counterpressure on the injection nozzle increases, bringing about an end of a preinjection phase.
  • fast opening of the storage piston 23 is required.
  • the intake side of the storage piston 23 is in communication with the high-pressure chamber 25 . At that instant, high pressure prevails inside the high-pressure chamber 25 .
  • the positively displaced volume In the return motion of the storage piston 23 , the positively displaced volume must return into the hollow chamber 42 of the spring holder. This can be done either via a communication with the return or at the inflow loop. If the positively displaced fuel volume is greater than the replenished quantity, the pressure in the hollow chamber 42 of the spring holder drops. If it drops below the vapor pressure, cavitation occurs. Also in the return motion of the storage piston 23 at the end of an injection event, the liquid column above the storage piston 23 is moved in the direction of the high-pressure chamber 25 . At that instant, the pressure inside the high-pressure chamber 25 is already in the vicinity of the vapor pressure, and as a result a fast return flow occurs. The high flow velocity of this return process causes the pressure to drop below the vapor pressure, and thus can once again cause cavitation.
  • FIG. 2 schematically shows a return flow throttle element, disposed between the storage chamber and the hollow chamber of the spring holder, for delaying the motion of the storage piston.
  • FIG. 2 in highly simplified form, shows a return flow throttle valve 35 , which is disposed between the storage chamber 24 of the storage piston 23 and the element chamber 25 of the spring holder.
  • the return flow throttle valve 35 which is shown schematically in the view in FIG. 2 , includes a valve body 37 , which is acted upon by a spring element 36 , and a permanently operative throttle restriction 44 , by way of which the storage chamber 24 of the storage piston 23 and the element chamber 25 are in fluidic communication with one another.
  • the pressure in the storage chamber 24 slowly decreases in the direction of the element chamber 25 . Because of the slow decrease, the motion of the storage piston 23 inside the storage chamber 24 is slowed down, so that replenishing fuel, for instance from the inlet bores 13 , can flow fast enough into the hollow chamber 42 of the spring holder B fast enough that the pressure there does not drop below the vapor pressure. If the pressure is kept above the vapor pressure there, no cavitation occurs, and so cavitation-free operation can be achieved.
  • the return flow throttle valve 35 allows an unhindered opening motion of the storage piston 23 in the storage chamber 24 , since the return flow throttle valve 35 is passable in the second direction 40 .
  • the high pressure in the entire high-pressure volume that is, inside the element chamber 25 , drops so far that the closing pressure of the storage piston 23 is reached, and its closing motion begins. Because of a pressure difference that arises between the pressure on the reservoir-side end of the return flow throttle valve 35 and the pressure on the high-pressure side of the return flow throttle valve 35 , that is, on the side pointing toward the element chamber 25 , the return flow throttle valve 35 closes.
  • the motion of the storage piston 23 can be slowed down to such an extent that the refilling of the hollow chamber 42 of the spring holder takes place in a way that avoids cavitation.
  • FIG. 3 shows a storage piston in its closing position on the sealing seat.
  • the storage piston 23 has moved by a stroke length 41 into its sealing seat 34 toward the element chamber 25 .
  • the hollow chamber 42 of the spring holder B is in communication, via the opening 31 , with part of the storage chamber 24 , and an end face 29 on the underside of the storage piston 23 has been placed at the distance of the stroke length 41 from the bottom of the storage chamber 24 , in the position shown in FIG. 3 .
  • the storage piston disconnects the element chamber 25 from the storage chamber 24 .
  • FIG. 4 shows the opening of the sealing seat at the storage piston when its opening pressure is reached.
  • the sealing seat, marked 34 on the top of the storage piston 23 opens.
  • the storage chamber 24 of the storage piston 23 is now filled via the opened sealing seat 34 and via the element chamber, and the storage piston 23 moves in the direction of the hollow chamber 42 of the spring holder B.
  • FIG. 5 shows the sealing off of the hollow chamber of the spring holder B by an end face, facing the sealing seat, of the storage piston.
  • V total V storage ⁇ ⁇ chamber ⁇ ⁇ 24 + ( ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ end ⁇ ⁇ face ⁇ ⁇ 29 2 ⁇ 4 ⁇ h storage ⁇ ⁇ piston )
  • Calculating the reservoir volume from the seat face area and the stroke length depends on how the valve is designed, for instance whether a cone seat or a ball seat is involved, which can mean different seat face diameters or averaged seat face diameters.
  • the goal is to design the spring prestressing of the spring element 36 such that the return flow throttle valve 35 can be kept in a defined prestressed position in the pressureless state, and a fast closing motion is reinforced upon closure of the return flow throttle valve 35 .
  • the task of the throttle cross section of the throttle restriction 44 embodied on the return flow throttle valve 35 is to slow down the pressure relief of the storage chamber 24 in the direction of the element chamber 25 in such a way that no cavitation occurs in the hollow chamber 42 of the spring holder B.
  • a pressure relief of the storage chamber 24 in the direction of the element chamber 25 should be attained that is fast enough that at the onset of the next injection cycle, the original pressure ratios, or in other words, a pressure equilibrium, is established soon enough.
  • a check valve can be used.
  • the check valve for instance containing a spherically shaped closing element 37 , which is acted upon by a spring element, preferably a spiral spring 36 , forms the limit shape of a return flow throttle element, in which the throttle is closed in the limit case.
  • a spring element preferably a spiral spring 36
  • the pressure in the high-pressure chamber 25 is subjected to high pressure by the pump piston 3 , in accordance with its reciprocating motion. With the check valve closed, the pressure on the reservoir side 24 remains at such a high level that the storage piston 23 stays in its opening position.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Fuel-Injection Apparatus (AREA)
US10/372,316 2002-02-25 2003-02-25 Noise-optimized device for injecting fuel Expired - Fee Related US6874705B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10207974.9 2002-02-25
DE10207974A DE10207974A1 (de) 2002-02-25 2002-02-25 Geräuschoptimierte Einrichtung zum Einspritzen von Kraftstoff

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US6874705B2 true US6874705B2 (en) 2005-04-05

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US (1) US6874705B2 (de)
EP (1) EP1338790B1 (de)
DE (2) DE10207974A1 (de)
PL (1) PL358850A1 (de)

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US7762478B1 (en) * 2006-01-13 2010-07-27 Continental Automotive Systems Us, Inc. High speed gasoline unit fuel injector
US11725618B2 (en) * 2017-02-02 2023-08-15 Woodward L'orange Gmbh Arrangement

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WO2003106836A1 (de) * 2002-06-13 2003-12-24 Siemens Aktiengesellschaft Pumpe-düse-einheit
EP1662133A1 (de) * 2004-11-26 2006-05-31 Siemens AG Einspritzventil

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US4750462A (en) * 1985-06-14 1988-06-14 Robert Bosch Gmbh Fuel injection apparatus for internal combustion engines
US4979676A (en) * 1988-12-31 1990-12-25 Robert Bosch Gmbh Fuel injection device for internal combustion engines
US5219122A (en) * 1991-08-30 1993-06-15 Nippondenso Co., Ltd. Fuel injection system for engine
US6305359B1 (en) * 1998-09-30 2001-10-23 Robert Bosch Gmbh Fuel injection valve for internal combustion engines
US6598811B2 (en) * 2000-07-10 2003-07-29 Robert Bosch Gmbh Pressure controlled injector for injecting fuel

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7762478B1 (en) * 2006-01-13 2010-07-27 Continental Automotive Systems Us, Inc. High speed gasoline unit fuel injector
US11725618B2 (en) * 2017-02-02 2023-08-15 Woodward L'orange Gmbh Arrangement

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EP1338790A1 (de) 2003-08-27
PL358850A1 (en) 2003-09-08
EP1338790B1 (de) 2004-11-03
US20030178001A1 (en) 2003-09-25
DE10207974A1 (de) 2003-09-18
DE50300129D1 (de) 2004-12-09

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